Building product and process for making the same



March 3, 1931. 4 R. E. BRAKE v 1,794,449

BUILDING PRODUCT AND PROCESS FOR MAKING THE SAME i Filed Oct. 8I 1925ATTORNEYS Patented Mar. 3, 1931 ff-UNITED* .Slfa12S. PATENT OFFICE fRALPH BRAKE-or JAMAICA, NEWYoRm-Assrenoa, BY MESNE Ass'IGNMEN'rsroAnaconnn -sMIEsconstruir7 -oENEW vom, n; Y., ak CORPORATION or DELAWAREv BUIEnING PEOEUCTAND PaocEss son MAKING kTHE SAME i Application aleaoctobers, 192e. .seriaiua 140.247.'

l This invention relates tothe manufacture of composite buildingelements suitable for roofing and otherpurposes and comprising a'non-metallic bas'e material anda sheathing of Weather-resistant metalappliedl to the surface thereof. 'More particularly, the inventionrelates to an electrolyti'c process for' the application ofmetalitobases of this type 1n the manufacture. of such'composite products. 10This process is of primary utility in the application ofcopper, .'Whchisthe metal principally used inbuilding elements of this kind, owing tothe resistance which copper oli'ers to corrosion, and its attractiveappearance, but the utility of the invention islby no means limited ztothe application of copper, nor to the use of any specific base material.

Owing to the high cost of Wooden shingles, and'their low lireresistance, numerous prepared v,roofin'gs are now in extensive use,these products being made of roofing felt, asbestos board, magnesitecompositions and the like.

rlhe felt product now enjoys the Widest popularity and it is made o1n afelt of suitable Weight arid thickness which is ordinarily saturated`With bituminous products, such as asphalt, andthen coated with a layerof asphalt which is capable ofwithstanding solar heat. 'Sometimes thefelt has an additional coating of granular material such as crushedslate, which improves its Wearing qualities and increases its resistanceto fire. Roofing products of this kind are in general satisfactory buttheir appearance on the roofvis somewhat monotonous and When notproperly made, the edges of the overlapping elements have a tendency'.in .time to Warp and curl,

making the roof unsightly and possibly subject to leakage. u A

to It has been proposed heretofore to use materials ofthis type in acomposite product which includes an additional layer of metal applied tothat area of the element Which is exposed to the Weather. A layer ofcopper thus applied 'wives the ro'ofthe appearance of being coveredwithcopper sheathing and such a roofis of handsome appearance, and of high-ire resistanceand long life. The difficulty involved in making such aroofing is to secure a good bond between the -base and metal, for

imperfect product and adds thetWo expand and/contract at different ratesand exposure to the Weather is likelyto cause ghe metal sheathing tocome vloosefrom the ase. 1

One proposa-lin an eHort to overcome lthis suggests the application ofthe metal to a base which has a roughand irregular surface due to theapplication of a layer of granularma-d `terial, such as crushed slate.,'The slate may be embedded partially in the aspha-ltcoating layer on thebase land the slate granules which are of substantial size projectbeyond the base and form crests andxdepressions. When the metal isapplied electrolytically over such a surface, the metal enters thedepressions and conforms to the irregularities of the surface, so that afirm mechanical bond is established.' In addition, the different partsof the metal sheet expand and contract in dilerent planes so that theexpansioneffect is not cumulative throughout the sheet in a horizontalplane.

`While the grit surfaced base coated' With metal is thus far superior toa plain surrfacedv product, attempts to apply the meta-lelectrolytically have met -with'numerous obstacles.' Anelectroconductivematerial. must be applied to the base' in order to permit theelectrodeposition of kthe metal and graphite, which is the simplest andAcheapest material to use, can be in a thin continuous film over allparte of irregular base sur face only- WithV considerable diiiculty.,and by the use of an adhesive. any failure to pra duce a film whichenters all the depressions and extends over all the crests results in anargcly to the cost of lproduction owing increased electrical resist-anceof the film.

This dilliculty has been overcome' by sub-5' stituting for the granularmaterial ordinarily used for roong purposes, anelectroconductive-inaterial of granular form, as distinguished from theelectroconductive powder or graphite ordinarilyl used.y rlhis materialmay be crushed petroleum coke, or the'like, and the individual piecesare about the same size as the particles of slate ordinarily used. ITheelectroconductive material is affixed to the base by being partiallyembedded in the coating layer of asphalt over'the felt in the lso 'j Itis the-object of usual way, and since the granules are of considerablesizeand are conductive, they 'provide the irregular surface on the baseand also the conductive surface neededfor the ele'ctrodeposition.` v 4In the use of the electroconductive granular material above mentioned Ihave found thatthe granules of the irregularlayer must be in closecontact throughoutthe surface of the base in onder that a substantially'continuous conductive surface may be provided on,v

which the metal is deposited, and any vfailure in this respect resultsin the production of a plating which has gaps and also the cost of `theoperation is high because of the low conductivity of the discontinuouscathode surface y this invention to pro vide a process of producing`building elements of the composite type electrolytically which may becarried onmore easily than those heretofore employed and which producesbetter results because the process'yields a' higher 'percentage ofperfect elements. This process involves the application' of anelectroconductive granular material to the surface of the base so thatthe'latter has the desired conductive surface and the irregular contour,but this granular materialv is select-ed and graded "so that 'a layer ofit applied to the base is substantially continuous i I with respect toits conductivity. This result 'vis obtained by preparing av granularmaterial in which the granules are of different sizes, selected so thatin a mass of granules the voids are considerably less than those presentin an ungraded grit. When such a material is applied to the surface ofthe base in the usual way, a layer results in -which each particle `isin close` contact with those adjacent, due

to the intermixture of large and small granu les, the smaller granulesfilling the spaces between the larger ones andl insuring this contact,while the large granules project from the base and produce theirregularity desired. The metal is plated over this granular surface inthe usual way.

Instead of using a graded grit'made of granules of different sizes insuitable proportions, I may secure the desired continu- 1ity in theconductive -lm by using an u'ngraded grit of particles of differentsizes just as it comes fromthe Crushers, where the grit masses have beenreduced to particles of a given maximum size suitable in a product ofthis type. But when such a grit is emy ployed, I first embed .the gritand then apply manner, and no considerable care in its apa thin film ofgraphite. The graphitemay be brushed on or applied in any convenientplication is required. The graphite thus applied finds lodgment in thecrevices between vthe grit particles, covers any asphalt exposedlbetween adjacent particles andsome of the graphite adheres to theexposed surfaces of the grit to provide with the grit a continuouselectroconductive layer. When ordinary grit and anadhesive are used, thegraphite or other conductor must be spread with extreme care and it isalmost impossible to make it adhere to the 'projecting points of thegranules, but in the new process,- this extreme care is not necessaryfor the graphite is intended only to bridge the spaces between theadjacent conductive particles and lodges readily between them.Accordingly, thel graphite which acts chiefly to augment theconductivity of the granular layer, may be lapplied'with great rapidityand by an attendant of only ordinary skill.

The invention includes not only a process of producing building productsof the composite type but also the improved product resulting from theuse of thisprocess. This product hasimportant advantages over thosepreviously produced in that a hrm bond between base and metal issecured, lthe metal layeris continuous throughout, and the product maybe made morev cheaply, owing to the lower number of imperfect elementsin a given run.

For a better understanding of the inven- -ion I'EGIGDC@ may be had tothe accompany-l ing drawing, 1n which,

Fig. 1 is a plan View of a rectangular building element made inaccordance with the yinvention', the layer of material on the base beingbroken awayfor purposes of illustration,

loo

Fig. 2 is a vertical s ectionalview on an enlarged scale, A K

Fig. 3 is a view similar to Fig. 2, but with the granular material shownsoniewhat enlarged, this material being graded as to size, Fig. 4 isa'view similar to Fig. 3, with the granular material ungraded and with`graphite or similar conductive powder also used,

Fig. 5 is a granular layer ready to be plated.

plan view of'a portion of the.

` ReferringV to the drawings, Fig. l shows l a building element inapproximately the `shape of an ordinary shingle, the element comprisinga base '1.0, a coating layer 11 thereon, a layer of granular materialy12 a'py standing solar heat without running'. This 'coating layer addsto. the waterproof qualivv `employ is referably of a'car'bonaceouschar-V acter andKV have found. that calcin'ed petroleum coke,metallurgical coke, coke 'obtained' from coal tar pitch," andlcarbonobtained by thejcalcining of anthracite coalare satis-` factory 'for-thei purpose. These materials possess lthe necessary velectricalconductivity,

are readilyobtainable, and easily crushed.

` I have fouhd'that the Siae ofthe particlesV ofconducting material torbeused to provide the cathode surface fon' the lelements 'over whichmetal is to be plated is of 7importance for vithe conductive materialused is made up of particles which arefvery fine, lit is difficult toproduce a layer of vsuch particles ofuniform thickness, in which all theparticles areun contactfunless excesslve quantities `of the vmateria-lare used. Then, when the layer is subjected to'pressure to cause theparticles to be-aiixed, many of the particles beeoine submerged and arethus quite useless. Unless r contact `is made betweengadjacentparticles, so that the layer is continuous asto its conductivity,- the.metal platingl is notv continuous and it isnot uniformlythick.vV'Also,1as

theconductivity of a non-continuous layer is low, the `cost for platingcurrent becomes high. jAlso, if material madeup ofnne particles `isusedto the extent ynecessary. to produce a continuous conductive film,some of the particleswill not become firmly affi-xed tothe base and thusthe bond between thedmetal coating yandthe base will be weakene c If theparticles employed are of too large a -size so that anappreciableportion of each particle is submerged in the plastic coating on thejbase, there is a likelihood .of laclr of contact, although the bondbetween such metal as can bedeposited, and the base, is quite good.

Accordingly, it will be seen the size of the granules has animportantbearing on the excellence of the finished product and itsmanufacture, and I have found that best results are obtained when thegranular material is linade up of particles of predetermined sizes, lsograded as to size and proportioned as to amounts as to produce a mixtureof fine and coarse, particles which may be applied in` a thin layer onthe face of a sheet in such manner that'the finer particles largely iillthe lspaces between the coarse particles so that eachuparticle contactswith those adjacent to it. By the use of such a mixture there aresecured maximum contact and optimum'conductivity in the granular layer.

In the grading of the granular material, I.

composition is satisfactory have found that almat'erial of-'thefelloWi-ng1V` 'Percent Retained jon a 14 mesh screen TA lO. ,ARetainedon a20 mesh screenrp 5.y Retained'on a.35 mesh screen e r l220,y Retainedon a-48 mesh screen 50.. Retained ona mesh .screen r 25 2i This' material is substantially ifreey fron? f1 f dust, which wouldinterfere Agreatly withv its a' application and also -With theadherencey of4 the mixture, and in a layer applied' to ay sheet; theparticles are in contact with eachother to,

such an extent that goodfconductivity is Jwf.8o

obtained.- -Y

'In Figs. 2 and 3,A abui'lding-product isshown made with 'granularmaterial: as abovev prepared, the illustrations being-'necessarilysomewhat diagrammatic. The base- `lO -y of' felt or othermaterial iscoatedwith thelayer of plastic material 11,then the graded-gran-` ularmaterial is spreadthereoverand'iallixed by the application of pressurewhichcauses a firm adherence yor partial submergence of` the grit.The'metal deposit v13 isv produced by ordinary electrolytic methods'andit willi bev seen that the metal'layer conforms to the irregular contourof the granular. surface,`

eac-h of the'particles of which-is a4 cathode f" surface on which metalcollects.` --The granulesinclude those' of coarse size Asuch asl/ly andfiner particles, such asie and 16, 'thesener particles lying between thecoarse ones.' The larger particles vproducethe major ir# regularitiesof'the 'surface which aiiord means for securing the mechanical `bond-be--tween base and metal, while thelineriparticles provide the contactbetween the larger;I i

particles so that the plating is vcontinuous and may be made at a.v lowcurrent cost. f f

.In some instances it may be desirable to'. .avoid the careful gradingand proportioning of the granular material to produce. a mix# ture ofthe proper characteristics,- and 'this can be.. done by havingthemateriall crushed to approximate maximum and l vminimum sizes, then.embedding this materialy in the coating on the base and iinallysupplementing the contact between the adjacent particles by anapplication of fine conductive material, This such as graphite or carbonflour. should be done preferably while the asphaltic coating is hot sothat any exposedparts ofv the coating will be covered by the graphiteand act as an adhesive therefor.

The application of the graphite may be conveniently eii'ected bysprinkling it on the sheet, then brushing or vvibrating the sheet sothat the graphite will settle into the interstices between adjacentgranules, and then removing the excess. This last operation prevents theloose graphite from intervening between the plating andthe embeddedgranules, thusdetriinentally affecting the bond.

In Fig; 4 there is shown a building element produced accordance with themethod just described. The base lOvhas the coating layer 11 in whichare'embedded the granules of the d conducting layer 12 over which isdeposited the metal layer 13. It will b e noted that the granules do nothave the grading as to' size and4 proportioning vasto amount present inthe case `of the granules shown in Fig. 3, but the open spaceswhichwould ordinarily occur between adjacent granules are now filled withgraphite as at 17. In some instances, thel graphite will contact with.exposed portions of the base coating as at 18 while in 'others thepowder will be wedged into the crevices, between adjacent granules. Ineithercase, the conductivity of the granular layer is greatly improved sthat the metal may be deposited very readily in the form of a continuoussheet of substantially uniform thickness which i's tightlyy bound to thebase;

Fig. 5 is a plan-view of a"small portion of `the surface. ready for theplating operation,

this surface being -madeof .particles graded' as to size and with' theparticles of different contour, there is1 a substantially continuouscontact'between each particle and those which are adjacent to it. YFurthermore, the area of such contacting surfaces throughout the sheet Ais quite' large, owing to the use' of the fine particles which lie inthe interstices between the larger ones. This results in a layer of goodelectrical conductivity and there is thus produced a continuous layer ofmetal of substantially uniform thickness, and owing to vthe highconductivity of the cathode surface,

the cost of plating current. used in the plating operation is kept at aminimum.

`The application of metal may be carried on by any'convenientelectrolytic process and may result in a plating over the entire surfaceof the. base or over predetermined areasthereof only. For thislatterpurpose,

V the conductive material may be limited to those areas where metal 'isto appear, as at 21, the remainder 22 of the base being coated with anon-conductive material, or'the entire base may becoated with conductivegranular material and the deposit limited to selected areas by the useof a stencil or mask during the plating operation. j

While I prefer to employ a non-metallic `conductive granular material,such as coke,

.it is possible 4to secure good results witha metallic material such asgranules or filings of copper, lead and other metals.

By employing thefconductive grit graded as to size'and proportioned asto amount and 4 lwith or without the graphite 'to secure an.

irregular conducting surface of the desired character, a superiorproduct is secured.

The presence of the fine particles .of the grit between thelargerparticles, or the l-odgment of thegraphite between adjacent gritparticlesiu the coating, tend to insure the production of a layer whichis substantially continuous with respect to conductivity and as. thelinterstices are thus partially filled either with fine grit orgraphite, as described,

thedepressions in thesurface are partially filled, so that thedepressions in the irregular surface are not so deep as would ordinarilyoccur. This has the effect of slightly smoothing out theirregularsurface, but does not interfere with the obtaining ofthe mechanicalbond. It does,h owever, result in securing a metal' film "which is ofsubstantially uniform thickness, because it is found that in an ordinarygranular layer vthe metal which enters the deep depressions betweenadjacent particles is not so thick as the metal which lies on thecrests. This is because the crests lie closer to the anode in theplatingcell and the metal has a natural tendency to collect on thesecrests for that reason., Whilethe more,- under these conditions, abetter cover- .v

age is secured because there is less'. superficial area to be plated inthe latter case than in the caseof al layer in which the interstitiallspaces are not partially filled. It is evident of course .that theseinterstitial spaces must not be completely filled, as this wouldinterfere with the strength of the mechanical bond, but it has beenfound possible to secure a satisfactory bond under the conditions Iabove suggest.

khere 1s a A production of the new material because a low percentage ofimperfect elements is produced due to thesuperior conductivityA of thecathodesurface. Furthermore, there is also a saving of energy because ina surface in which the particles are not in contact it is possible, by4continuing the fplating operation, even-- tually to secure a lm which iscontinuous throughout the base, but this requires that the metal platingshould be built uv so as to bridge the points not in contact, an inmanyinstances this continuous film of metal can only bevsecured by carryingon vthe plating operation to a point such that the thickness of the filmat soniepoints on the base is 'much' greater than is desired.

Owing to the fact that the new material includesl the rough irregularsurface on which further saving in the cost of arcate-e the metal isplated, the product is of attractive appearance because the metalcoating is given a texture and the product is of long life, due to thecomplete protection aorded theA base by the metal plating.

l claim:

l. A process for producing building elements suitable for roofing andsimilar pur poses, Which comprises crushing and gradingclectro-conductive granular material to produce a mixture containingselected amounts of particles of different sizes While substan tiallyeliminating dust, applying a layer of sucli graded granular material tothe surface of a base, said layer having high electrical conductivityand giving the base an irregular surface, applying a conductive powderthereover, the powder largely occupying the interstices between adjacentgranules, and electrodepositing a layer of metal over the conductivesurface soformed.

2. A building product suitable for roofing and other purposes, Which comrises a base, a layer of material affixed to t e surface of the base,this material being graded selected amounts of particles of dierentsizes, ex-

' cluding dust to produce a layer in which each particle is in goodelectrical contact With the particles adjacent to it, certain of thesepar-v ticles being of a size sufficient to give the layer lan irregularsurface, and a coating of metal over the said layer and conforming tothe irregularities thereof. y.

3. A process for producing building elements suitable for roofing andsimilar purposes which comprises affixing to the surface of a base alayer formed of a graded mixture of granules of electrosconductivematerial in Which mixture all of the granules will pass through a screenof 14 mesh and a substantial proportion Will be retained on a screen of48 mesh, dust being substantially absent from themixture,.and.electro-depositing a film of metal over the granular layer.

4. A process for producing building elements suitable for roofing andsimilar purposes, which comprises grading electro-conductive granularmaterial to produce a mixture including a substantial proportion ofgranules of substantial size and a pro ortion of iner granules,particles of dust fineness being eliminated in the grading operation,aflixing this mixture to the surface of a base to provide a layer ofirregular surface contour due to the presence of the larger granules andof high electrical conductivity due to the finer granules lodged betweenand electrically connecting the larger granules, and electro-depositinga coating of metal over 0 the granular layer.

In testimony whereof I aliix my signature. RALPH E. DRAKE.

